Studies on rabbit bactericidal factors: For the forthcoming year, goals include: (1) further characterization, including amino acid, lipid, and carbohydrate analyses. Along these lines, a fluorometric method for the quantitation of amino sugars has been developed (manuscript submitted to Analytical Biochemistry); (2) a more detailed examination of the effects of the primary factor on susceptible cells, with the ultimate aim of determining the biochemical mode of action of this factor, as well as the time at which the cell becomes committed to death; (3) an examination of eucaryotic cells, such as yeasts, for their ability to withstand incubations with the primary factor, in hopes that this may lead to an understanding of the specificity and action of this serum component. Several other bacterial strains will also be examined. Studies on human bactericidal factors: The goals of this investigation for the forthcoming year are: (1) to analyze the carbohydrate and peptide components of the non-lysozyme bactericide; and (2) to determine the biochemical mode of action.